This park, made up of four parcels of land, was formally the 903 hectare Te Oka Farm, a coastal headland property adjoining Tumbledown and Te Oka Bays in the southern bays sector of Banks Peninsula.

The purpose of acquisition was for the protection and enhancement of the area’s biodiversity, and to provide recreation opportunities.

Te Oka Reserve covers an altitudinal range from sea level up to about 680 metres elevation. It provides the opportunity for sea to summit ecological restoration.

The park contains two high quality biodiversity sites covering approximately 280 hectares, as well as a much larger area with significant conservation value.

There are about seven hectares of old growth podocarp forest, which is a remnant of the original pre-European forest that once dominated Banks Peninsula. There is also a considerable amount of tōtara regeneration, with trees from three to five metres in height scattered through both the two valleys in the park.

All four of the common Banks Peninsula podocarps are present in the park, including kahikatea, matai, lowland tōtara and Halls tōtara.

The park contains three plant species that are listed on the New Zealand threatened plant list. One of these, a fern ally called Tmesipteris, has two identified populations in the park. It appears to be very uncommon and has been given a threat rating of ‘Nationally Critical’, the highest level of threat.

Te Oka Stream has very high values for its freshwater fish (seven species) and Tumbledown Stream has possibly slightly higher values as it has two more species than Te Oka (nine species).

Park values for recreation purposes include:

A landscape containing a variety of grassland, forested and coastal environments